Adjustable turning and boring tool



my 26, 1938 F. c. JEARUM $25,010

ADJUSTABLEVTURNING AND BORING Toor.

Filed Juy 11, 1936 l 11.3.10. 5` es zwvewoz F. C.' Jfmeu/vl Patented July 26, 1938 7 ,natos- PANT erica 2.125,0@ ADJUSTABLE TURNING AND BORING T061.

Frederick Charles Jeamm, Chipstead, England Application July 1l., 1936, Serial No. 90,051' y i 'In Great Britain August 17,1935' 'J 1e claims.

This invention relates to Aadjustable turning and boring tools and, more particularly, to turning and boring tools having cutting bits adjustable along and relative to a supporting shank 5 adapted to be clamped .in tool holders, boring bars and the like. tomary method of using turning and boring tools having super-hard tips of diamond or tungsten carbide typethat in the first place the tip is l0 liable to be `lamaged in the adjusting operations,

usually performed by tapping backward' or forward, and in the second place that the haphazard result of adjustments so performed tends to vitiate the accuracy of cutting of which such tools are capable. It is the purpose, therefore,

of the constructions exemplifying the present 1nvention, to eliminate doubt as to the degree vof adjustment performed by employing positive and graduated adjusting means for effecting and 2o controlling the setting of the toolto the work.

Accordingly, the invention provides an adjustable tool-bit of the kind described above having a member bearing a cutting tip of the type referred to, a body member whereby the bit may 25. be clamped in an operating position and definitely progressive adjusting means for adjusting the position of said cutting-tip bearing member with respect to said body member substantially in the direction of the depth of cut.

in order to illustrate the nature of the means provided in accordance with the invention, embodiments are herein described with; reference to the drawing which accompanies this specification, and wherein,

Fig. l is a longitudinal elevation of an adinstable tool `bit intended for use in` a boring bar and provided with means for giving adjust mentV by rotating a graduated head, Fig. 2 is a rear end elevation thereof, 40 a portion of the tool in longitudinal section,

Fig. 4 is a view in elevation and longitudinal section of a simplied form of the invention,

Fig. 5 is a longitudinal horizontal section of a modified tool provided with a differential adjusting means by which a much finer degree of adjustment is made possible,

Fig. 6 is a longitudinal vertical sectional view of the Atool shown in Fig. 5,

Ng. 7 is a longitudinal vertical section of a tool constructed to provide for both coarse and iine adjustments independently.

Fig. 8 is a longitudinal elevation .cfa key for adjusting the tool shownl in Fig. 7, and

Figs. 9 and 10 are respectively longitudinal horizontal and vertical sections of a modification of the construction shownin Fig. 7.

In Figures 1, 2, and 3, a shell, I, is adapted to be clamped in holding means in the toolholder w or boring bar in which the tool is required to be lili It is a. drawback in the cus-4 Fig. 3 is a view similar to Fig'. l but showing (El. Ztl- 96) used. A nose, 2, carrying an inserted, Superf hard tip, 3, is slidable within the shell,f l, and is furnished at its inner end with a tapped shank,

' 4, which engages with a threaded bolt, t, having a transverse keyway, t, at its rear end, the screwed portions being preferably left handed. The adjusting head, l, has a spigot, t, by which the head, l, is centered in the shell, i, and has a transverse key, il, protruding through the internal collar, i, of the shell, l, and engaging with the said keyway, t. 'A screw, il, clamps the head, 7, to the bolt, 5, thereby retaining the key, 9, in engagement with the keyway, 6, and preserving the bolt; 5, in constant/ axial relation to the internal collar, i il, and thus to the shell, l..

The head, is provided, as shown in Figure 2,

' with a hexagonal recess, I2, by which it may, be

rotated with the employment of a hexagonal key of well-known type, and the degree of adjustment may he read by noting the relation of the graduations, i3, on the head, "l, to the reader mark, iii, on the adjacent part of the shell, i.

in order to prevent the nose, 2, with its shank,

It. This arrangement admits of the tool bit be-l ing readily'taken apart when the key, i5, is pressed into its pocket, it, sufficiently to disen gage its feather, il, from the slot, i8.

The slots, lil, in the shell, i, Figure 1, also allow a slight contraction of the shell onto the shank, d, under pressure of the clamping means of the toolholder, thereby providing for the greater stability of the shank, 4, and the nose, 2, in which the cutting tip, 3, is mounted.

In Figure 4, is shown a simplified form which is adequate for some purposes. Here the vcutter head, 2l) has its shank, 2i, threaded immediately behind its shoulder and a graduated ring, 22, is tapped to fit the shank, 2|. The rear end of the li, from rotating with respect to the shell, i, a

shank, 2l, is tapped for a shouldered screw, 23,

which passes through a collar, 24, inside the shell, 26. Between the head of vthe screw, 23, and the saidcollar, 24, is aspring, 26, tending to withdraw the shank, 2l, into the shell, 25. The extent to which this is permitted is determined by the adjustment of the ring, 22, as it bears against here, the bolt, 36, which is tapped/into the shank, 29, with a thread of a particular pitch, is constrained axially or the shell by having its head, 3l, threaded with a somewhat finer pitch and engaging with a similar thread tapped'into a portion, 32, of the shell, 2l, itself.

In this case, both screws are left handed. The bolt, $0, is also slotted `as shown at, 33, to embrace` a. Sat stem, 36, which is furnished with a transverse keyway, 35, in a manner similar to that of the bolt, 5, of Figure 1, the keyway, 35,.

engaging with "a key, t6, formed on the spigot, 3l, ci the adjusting head, 3d. A screw, 39,

' clamps the head, 38, to the stem, til, and retains both in the shell, 2l, as in the former case.

supposing that the shank, 29, and the bolt, 30,

have e. thread of slightly coarser pitch than that on the head, Si, and in the portion, 32, of the shell, 2l, then the rotation of the bolt, 30, by the stem, 3d, will move the shank, 29, in one turn, a distance corresponding to the diderence between the pitches ci the respective threads. Thus, in a particular case, if the bolt threads are 46 per inch, and those on the head of the bolt 50 per inch, one turn or the bolt will move the shank V40-%0=V;00 oi an inch. If, now, the head, 38, be graduated with 50 divisions, each divisionY will represent a movement di the shank, 29,; oi domo of an inch.

In this construction also, a sprung key, $6, pre--l vents rotation of the shank, 9, inthe shell, 2l.

Figure 7 illustrates a construction similar to that shown in Figures 5 and 6, but in which the coarser screw can be'employed independently to give preliminary settings upon which tine adjust- Y ments may be superimposed subsequently.

' shellyl, and has a spigot, inpassing through,

and the bolt, di, has a long slot, di); An operate" ing key 5t (Fig. 8) is formed partly as a hat blade 5I and partly as e hexagonal body 52.

The key-body, 52, has, slidably mounted upon it, a collar, 53, lightly sprung to bear against the head, 47, when the key is inserted into the latter. When the key' is fully inserted, the blade, 5I, engages the slot, te, in the bolt, 4i, and the body, S2, engages the head, 4l. Now, if the key is turned, the head, tl, the sleeve, d2, and the bolt, 4|, all turn as a solid and the adjustment or the shank, 43, will be by the ccarser screw, only.. Should the key be allowed to emerge somewhat, so that the body, 52, is clear of the head, 61, and the collar, 53, still bears ,against the head, Il. operation ofthe key causes the bolt, Sl, only,to

., rotate and the adjustment will be made as in the construction shown in Figures e, 5, and 6, the degree of` adjustment being indicated by `the graduations, 54, on the collar, 53, and the reader mark, 55, on the head, 4l.

rn a further modmcauon shownin Figures e and 10, the head, 56, is so fitted to the sleeve,

This sleeve, 42, iso

tongue, 3,3, the free end of which, was a portion o! the collar, 58. The exterioror this tongue, 83, is somewhat tapered inwards to its free end, as shown by the line, 60, vand the inner portion o! its tree end is relieved so that a ball, 3l, having a diameter equal to the widthof the tongue, may be retained in one of the pits, 6,2, in the sleeve, 31, by the said tongue. With this construction the key, 61, does not require to be tted with the former sliding graduated collar,l as the head, 56, is made to serve for measuring either the coarse or the ne adjustment.

In 4this case, a blade member, 65, is recessed at its rearward end, 56, into the head, 56, so as' to turn therewith, and permanently engages the slot in the bolt, 64, passing freely throughthe hexagonal hole in the sleeve, |51.

The thickness of the blade is such that the operating key, 6l, when slotted as shown, may be inserted through the head, i8, and engages the hexagonal hole, 85, in the sleeve, 51, thus being enabled to turn the head, the sleeve, and the bolt, as a solid, to give the coarser adjustment. When the key, 61, is inserted, to engage the head,

. 56, only, and not the sleeve, the latter' is retained stationary by the ball, 6I, and the rotation of the head, y56, with the blade, 6E, effects the liner adjustment.

It will be seen that when the tool is used ln a boring`*bar, the importance of the `entire construction being kept within the normal diameter lof the tool blt is considerable, as is also the transfer of the clamping pressure to the shank itself, whereby the nose leaving the cutting tip, 'is prevented from loss of rigidity.

y What I claim is:-

1. A tool or the class described, comprising a tubular shell, a tool holding head projecting from the forward end of the shell and having' a shank extending axially into such end and supported on the inner wall of the shell, and screw threaded means located axially o! and within the shell and cooperating with the shell and the rear end of the shank to hold the shank and the head against axial,y movement forwardly and rearwardly 'and including a rotary member for adjusting the shank and head axially of the shell, and means at the rear end of the shell having a key and slot rotating connection with the member, the shank continuously fitting the inner wall ci the shell from a point closely adjacent to the head to a. point remote therefrom whereby securely to support the head in retracted and extended positions.

2. A tool oi the class described, comprising a tubular shell, a tool'holding head projecting from the forward end of the shell and having a cylindrical shank extending axially into such end and fitting the inner wall of the shell from said forward end rearwardly, screw threaded means within the shell and in threaded engagement with the rear end of the shank, calibrated means at the rear end of the shell for rotating the screw threaded means and adjusting the head longitudinally a predetermined amount, and means connecting the calibrated means to the screw threaded means whereby rotation oi' the former rotates the latter and whereby the latter .Vis held against .longitudinal movement.

3. A, tool of the class described, comprising a tubular shell, a tool holding head projecting from the forward end o1' the shell and having a cylindrical shank extending axially into such end and tting the inner wall of the shell from said forward end rearwardly, and a screw threaded member located axially of andwlthin the shell,

said member having threads of different character cooperating respectively with the shelland the rear end of the shank.

4. 'I'he tool dened in claim 3 in which said threads are of dillerent pitch and in threaded engagement respectivelywith the shell and the rear end of the shank. l

5. A tool of the class described, comprising a tubular shell havingv a cylindrical bore therein, a tool holding head projecting from the forward -end of the shell and having a cylindrical shank siidably tting the -cylindrical wall of the bore from the forward end of the shell rearwardly, a

screw in the shell having two threaded portions shell so connected tov thev screw as to cause the vscrew to rotate with the member.

6. The tool deiined in claim in which said means includes a member having engagement with the screw and preventing their relative rol tubular shell having a longitudinal bore theretation but permitting relative'movement longitudinally of the shell, and means holding the rst and second named members from separating movement longitudinally of the shell.

7. A tool of the class described, comprising a tubular shell having a longitudinal bore therethrough, a tool. holding head projecting from the forward end of the shell and having a shank ex tending into the bore and supported for longitudinal movement on the wall thereoi, a sleeve in the shell rearwardly of and in alignment with the shank, a screw in the shell having two threaded portions respectively of relatively coarse and fine `pitch and respectively in threaded engagement with the rear end of the shank and the sleeve, and means preventing axial movement ofI the sleeve, the sleeve and screw being rotatable as aunlt and the screw being rotatable independently of the sleeve.

8. A tool of the class described, comprising a through, a tool holding head projecting from the forward end o! the shell and having a shank extending into the bore and supported for longitudinal movement on the wall thereof, a sleeve in the shell rearwardly of and in alignment withv the shank, a screw in l the shell having two threaded portions respectively of relatively coarse and ine pitch and respectively in threaded en- Easement with the rear end of the shank and the sleeve, means preventing axial movement of the sleeve,` means for rotating the sleeve andfscrew as a unit or rotating A the screw independently of the sleeve, and nieans for indicating the degree o! tool head adjustment eilected by such rotation. v9. A tool oi' the class described. comprising an elongated shell having a longitudinal boretheren shank and shell to hold thevshank and head against axiall movement including a rotary member for adjusting the shank and head axially of the shell.

- 10. The tool defined in claim 9 in which the shell is laterally 'compressible into binding engagement with the shank. i

Yll. Ihe tool dened in claim 9 in which the shank is prevented from rotation within the shell by a key within the shank spring-pressed outwardly into a slot extending longitudinally of and through the shell.

12.`A tool ofthe class described, comprising a tubular shell having a bore therethrough cylindrical at and rearwardly of its forward end. a tool holding head projecting from the forward4 end' of the bore and having a` supporting shank cylindrical therealong to a point closely adje.m cent to said head and slidably ttlng within the bore, and screw threaded means located axially of the shell and cooperating with the shank and shell to hold the shank and* head lagainst axial movement rearwardly and including a rotary member for adjusting the shank and head axially of the shell, the shell being slotted longitudinally whereby rendering it compressible into binding engagement with the shank.

13. Atool of the class described, comprising a tubular shell havinga longitudinal bore therein of greater diameter than the thickness of the shell wall and cylindrical from the forward end of the shell rearwardly, a tool holding head of a radial size substantially corresponding with the shell and having a reducedI cylindrical shank extending axially into the forward end of the bore vand supported on the wall thereof from the forward end of the shell rearwardly, and screw threaded means located axially of and within the shell and cooperating with the shank and shell to adjust the shank and head to different axial positions andhold them in such positions relative to the shell, the cylindrical shank being constructed continuously to nt the walls of the bore from a point closely adjacent to the head to a point remote therefrom whereby securely to support the head in retracted and extended positions.

--14. The tool defined in claim 13 plus calibrated means at the rear end of the shell and of a radial size substantially corresponding with the shell for rotating the screw threaded means and indicating the resulting adjustment of the head.

15. A tool of the class described, comprising a tubular shell having a cylindrical bore therein, a tool holding head projecting from the forward end of the shell and having a cylindrical shank slidably fitting the wall of the bore from the forward end of the shell rearwardly, a screw in threaded engagement with the rear end of the shank, a shoulder integral with the shell and preventing rearward movement of the screw in the bore, and means including a rotary member connected to' the screw as to prevent forward movement. thereof and .cause the screw to rotate with the member.

16. The tool dened in claim 15 in which said means includes co-engaging transverse shoulders between the screw and member, and means holdl ing the member and shell from separating move-A 

